A chest X-ray unit typically includes an exposure station having a pair of intensifier screen members that receive a film sheet between them. While older units require individual hand loading and unloading of a sheet between the intensifier screen members, greater efficiency can be obtained by utilizing a supply film cassette to supply one film sheet at a time, and a loading mechanism for automatically loading the sheet between the intensifier screen members in a daylight environment. Further efficiency can be obtained by utilizing a receiving cassette to automatically receive and store each film sheet after it has been exposed. The simplest arrangement is to position the supply cassette above the exposure unit and the receiving cassette below it, so that sheets can drop by gravity from the supply station to the exposure station and then to the receiving station. However, such an arrangement results in a tall structure that is cumbersome to move up and down to the height of a patient's chest, and which interferes with the movement of patient-holding gurneys or other equipment in the floor area under the apparatus. An X-ray system of moderate height which incorporated automatic supply and/or receiving cassette stations, would greatly enhance the acceptability of labor-saving X-ray systems.